Butyl and polyisobutylene products stay soft and tacky, block water vapor extremely well and stick to most surfaces. They appear as concealed lap sealants in metal roofing and siding, as tapes for flashing and window installation, and as the primary seal in insulating glass units. They are not suited to exposed moving joints because they do not recover after stretching.
Butyl tape in every endlap on the metal panels, two rows, it stays tacky and the lap never sees sun.
Also heard as
- butyl tape
- PIB
- polyisobutylene
Related terms
IGU
Insulating glass unit, two or more lites sealed around a spacer with a dry air or gas space between.
Strip-in
To seal the flange of a flashing or fixture to the surrounding membrane with an overlapping strip of tape or sheet.
Sealant
A material that fills a joint or gap to stop water and air, while accommodating movement.
Peel-and-stick
Field name for self-adhered membrane: rubberized asphalt or butyl sheet with a release liner on the back.